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Professor H. M. Evans, when making a study of the reproductive capacity of rats at the University of California in 1922, found that animals given a diet containing all the then known vitamins failed to produce normal litters. This observation indicated that another vitamin was required for fertility and subsequently led to the recognition of vitamin E. The vitamin was known to be present in lettuce and wheat germ, since when either of these were added to the rats' feed their fertility was restored. Subsequently, in 1936, by a lengthy procedure for concentrating the vitamin, Evans was successful in isolating the pure substance from wheat germ oil. It was identified as an alcohol with the chemical formula G29H50O2 and found to be fat soluble. At the suggestion of Professor G. Calhoun, Evans introduced the name “a‐toco‐pherol” for the pure compound (from the Greek tokos = childbirth, phero = to bear, and “‐ol” indicating that the substance is an alcohol).

Multiple sclerosis, otherwise known as disseminated sclerosis syndrome or MS for short, is so‐called because it involves a multiple scarring, or ‘sclerosis’, of the central nervous system. The onset of the disease is often difficult to identify because it begins with intermittent episodes of attacks which may be quite mild. There are also periods of remission so that attacks may be forgotten and not related to the disease. MS is more prevalent in females and initial episodes usually occur between the ages of twenty and forty years of age.

So it was that St Paul, who knew a great deal about athletics, advised his correspondents in Corinth nineteen hundred years ago but the advice might equally well be given to‐day. Every athlete knows the importance of exercising his body in training but may overlook the contribution that an appropriate diet may make to his performance.

It is well known that the human body requires many different nutrients for its growth and healthy maintenance. Some nutrients are required in relatively large amounts, namely the carbohydrates, fats and proteins, whilst others are needed only in small amounts. The latter include the vitamins, minerals and trace elements. The requirement of each different nutrient has been ascertained with a reasonable degree of accuracy for the varying ages and types of mankind. For optimal health the requirements of each nutrient have to be met in the food eaten by every individual.

In 1987 the Medical Research Council's Dunn Nutrition Unit celebrated its Diamond Jubilee.1 What was the background to the Council setting up a Nutrition research establishment in 1927? Why was Cambridge chosen and why is it called the Dunn?

During the early years of the present century it was suggested that, besides all the then known nutrients, “accessory food factors” were required for the health and growth of man and animals. McCollum and Davis showed in 1915 that at least two such factors were necessary. One was present in fatty and the other in non‐fatty foods; they were named “Fat‐soluble A” and “Water‐soluble B” respectively. At the instigation of Drummond these factors were renamed vitamin A and vitamin B. Subsequently the so‐called “vitamin A” was shown to be a mixture of the factor known to cure xerophthalmia (i.e. vitamin A) and the one that was then shown to cure rickets.

Scurvy is probably one of the oldest recorded diseases encountered by man. When Magellan circumnavigated the world in 1522 the majority of his men were stricken with the disease. In 1535 Cartier noted that it could be cured by a decoction of spruce tips. Even so the disease continued to be a formidable problem on long voyages for many years to come. Thus during Anson's voyage from 1740 to 1744 a total of 626 men are reported to have died of scurvy whilst rounding Cape Horn. Dr. James Lind, Physician to the Fleet in the seven‐teenth century, was largely instrumental in overcoming the problem. He rediscovered the cure by pine needles, and by citrus fruits, and greatly extended their use for preventing the disease.

Phytic acid and mineral absorption. In 1925 Sir Edward Mellanby demonstrated that when puppies were given a diet poor in vitamin D and calcium, and containing large amounts of bread, they developed rickets. At first this was thought to be due to the growth promoting properties of the bread which allowed the puppies to grow at a rate faster than their bones could lay down calcium. However, it was later shown to be caused by the presence of a compound of inositol combined with six molecules of phosphoric acid. The formula of this compound, which is phytic acid, is shown in the figure.

Anaemia is a disease characterised by a reduction in the number of red cells in the blood, or in the amount of the iron‐containing red pigment, haemoglobin. Various types of anaemia are known, thus macrocytic anaemia is the name given to the condition when there is an increase in the average size of the red cells in the blood. It is now known that two vitamins, viz. folic acid and vitamin B12, are involved in the prevention of some anaemias.

In the last article we saw how Goldberger, in 1926, demonstrated that the ‘Water soluble B’ factor of McCollum and Davies contained more than one vitamin. He showed that pellagra was associated with the lack of a vitamin and that the latter was distributed in a somewhat similar manner to the anti‐beri‐beri factor. However, Goldberger demonstrated that there was an essential difference between the two factors: the one preventing pellagra was more stable to heat. He called it the pellagra‐preventive, or P‐P factor.